OpenTelemetry (optional)

MCP-Bastion can export spans to an OTLP endpoint for tracing.

Setup

Set the OTLP endpoint:

export OTEL_EXPORTER_OTLP_ENDPOINT=http://localhost:4317

Install the optional OTEL dependencies:

pip install mcp-bastion-python[otel]
## or
pip install opentelemetry-api opentelemetry-sdk opentelemetry-exporter-otlp-proto-grpc

Behavior

• When OTEL_EXPORTER_OTLP_ENDPOINT is set, every tool call is recorded as a span (mcp_bastion.tool_call) with attributes: mcp.tool, mcp.action, mcp.latency_ms, and mcp.error when blocked.
• The audit export callback (used when audit is enabled and metrics are wired) calls record_tool_span so no extra wiring is needed if you use build_middleware_from_config() or make_audit_export_callback().

Metrics

Dashboard Prometheus endpoint (GET /metrics) is the primary way to scrape metrics. For OTLP metrics export you can run a collector that scrapes the dashboard or forwards from your existing pipeline.